I got to the Imperial Guards on the Death Star and my saved game disappeared. Not best pleased about having to grind past all these frustrating bosses once again. Kazdan thingamajig killed me a few times in one shot, and I didn't know three measly little stormtroopers could be such an obstacle for a Sith Lord.
But Maris Brood popping up during the Rancor battle is the most unfair part of it, as you can't block her attacks! The Rancor doesn't damage me at all, but it takes so ridiculously long to kill it, it's a wonder I haven't thrown my Xbox out the window. It's not the only game to do this, but I think it stacks the odds to far in favour of the enemies. I know it's the highest difficulty, but I will get no enjoyment out of beating it, just relief that it's over.